import java.util.Stack;

/**
 * Created with IntelliJ IDEA.
 * Description:
 * User:岁亮亮
 * Date:2024-05-28
 * TIME:13:56
 */
public class Test {
    public static void main(String[] args) {
        String str= "4";
        Integer i = Integer.valueOf(str);
        char ch = str.charAt(0);
        char sh = '4';
        Stack<Integer> stack = new Stack<>();

        System.out.println(ch==sh);
        System.out.println(ch);
        Integer integer = Integer.parseInt(str);
        System.out.println(i);

    }
}
